Things You'll Need

Instructions

Declare a Variable in JavaScript

1

Choose a variable name which meets JavaScript guidelines. Variables names can contain only numbers, letters, or underscores, and must start with a letter or underscore. The are case-sensitive: the variable ABC is distinct from abc.
2

Find the best place to declare your variable. Variables declared outside of a function are available to all commands throughout the entire script, and are called "global" while variables exclusive to a specific function are "local", declared inside the function.
3

Declare the variable using the var command, as follows:
var my_variable;
4

Add additional variables to the declaration for compactness:
var one_var, two_var;
5

Specify an initial value for the variable by following it with an equal sign and the value:
var zero=0;